Sump Pump Batteries

Factors Influencing The Cost of a Backup Sump Pump

Pumping Volume

How much water your backup is able to pump is important because a backup sump pump  is supposed to step in and take over the duty of keeping your basement dry when your  primary pump is unable to perform. If your primary pump has 50 gallon per minute (GPM)  pumping power during the worst storms, does it make sense to have a 35 GPM backup?

Matching pumping volume might require you to buy a bigger backup, but during the worst  storms when the power fails do you really want to rely on a smaller backup pump to keep  you dry?

So how long will a battery backup system keep your basement dry? That depends on how  much water is entering your sump basket (which determines how often the pump will run).

Everything to Know About Sump Pump Battery Backups

Cause of Sump Pumps To Fail

The most common reason for pump failure is a power outage, not some problem with the  pump itself. Common events besides power outages can also cut off the supply of  electricity. For example, lightning can trip GFCI outlets, or someone can unplug the pump  and forget to plug it back in.

Assuming the power stays on, sometimes the pump itself fails. Many inexpensive sump  pumps are simply too small to handle the flow from a major downpour or rapid snowmelt.  And because inexpensive pumps are built with less durable materials, they lose pumping  efficiency. So the pump runs more often and burns out early. Or the motor runs but the pump  doesn’t eject water.

Float switches are also a frequent cause of pump failure. “Wide angle” tethered float  switches, the kind that free-float around the sump basket, are the biggest troublemakers.  They swirl around the sump basket, making them far more likely to get trapped against the  pump, discharge pipe or power cord. Once trapped, they can’t switch on the pump.  Inexpensive switches can also simply wear out or cause motor burnout.


A dead pump can lead to disaster. Here's how to avoid trouble

Backup Sump Pump Cost

How long do sump pump batteries last?

As a general rule of thumb, during a power outage most new fully-charged batteries will  last roughly 5-7 hours of continuous pumping and roughly 1-3 days of non-continuous  pumping depending on the frequency.

How often should sump pump battery be replaced?

every five years

Battery must be replaced every five years (and costs about $100). 

Quality backup sump pump systems range from $1,000 to $4,500 installed.